Fleet management and cargo shipping companies use tracking devices installed on cargo containers to keep track of the location of the containers. Such devices typically use GPS receivers to determine location coordinates and wireless data transceivers to transmit location information and alert messages via wireless networks to central cargo management servers. The cargo containers may be twenty foot long or forty foot long foot shipping containers well known in the art or they may be cargo trailers of about the same dimensions that are pulled by tractors.
In most cases, the tracking devices are self-contained units that are mounted to an outside surface of a container or trailer. There is a need for cargo management personnel to know when a cargo tracking device is removed from a trailer or other cargo container. There is also a need to know whether or not a cargo container has been loaded onto a trailer.
Current solutions are indirect, expensive, hard to install, have limited sense distances, lead to false alerts, and can result in alerts that are not received when something happens.
What is needed, therefore, is a cargo tracking device that overcomes the deficiencies of the prior art.